Disposable fluid circuit assemblies are typically used for collecting, storing, separating and/or other processing of biological fluids, such as blood from a donor, patient or other source. They are commonly preassembled, presterilized and fully disposable for safety and convenience. These assemblies may include plastic tubing, containers, valves, flow control modules and the like for controlling fluid flow through the assembly. When employed on the collection or processing of blood and blood components, these assemblies typically include a venipuncture needle for insertion into the arm of a donor or patient. The needle is usually attached to one end of a flexible plastic tube which provides a flow path for the blood to the rest of the fluid circuit assembly. The other end of the plastic tube may be attached, either directly or indirectly, to one or more plastic bags or containers for collecting the withdrawn blood or a component of blood, such as concentrated red cells or platelets, or plasma. Such fluid circuit assemblies may be employed in manual blood collection procedures, where whole blood is collected from a donor for later off-site processing, or in automated procedures, where the fluid circuit is mounted on a reusable device, such as a centrifuge or other separator, that automatically controls flow of blood or components through the assembly. When used for blood collection, these fluid circuit assemblies are commonly called blood sets or apheresis sets.
The fluid circuit assembly may also include a sampling sub-unit to provide for collection of a sample of blood or blood component, which can be used for testing. It is known to use pierceable junctions in the fluid circuit to allow the user to extract a sample at the desired location. This has associated with it, however, a risk of accidental needle puncture as well as undesirable pooling of the fluid at the location of the sample port.
As shown in U.S. Pat. No. 5,496,301, it is also known to use a sample bag or pouch that is connected by a length of tubing to a sample tube holder for cooperating with vacuum sample tube, such as the Vacutainer™ sample collection tube marketed by Becton-Dickinson Co. of Franklin Lake, N.J. The holder includes a cylindrical shield and an internal needle within an elastomeric sheath for cooperation with the Vacutainer™ tube.
The arrangement illustrated in the above patent, however, is not as conductive to ease of manufacture or economy of packaging as may be desired. Also, in addition to other apparent shortcomings, it requires manual manipulation, such as inversion and the like to retrieve a sample and may not allow for easy and rapid withdrawal of the entire sample contained in the sample bag.